Solenoid initiating mechanism for machine guns or other devices



'July 10, 1945- L A vERN E. QUINNELL ET AL 2,380,262

SOLENOID INITIATING MECHANISM FOR MACHINE GUNS OR OTHER DEVICES FiledMay lO, 1941 2 Sheets-Sheet 2 Patented July 10, 1945 SOLENOID INITIATINGMECHANISM FOR MACHINE GUNS OR OTHER DEVICES La Vern Edward Quinnell andJohn C. Koonz,

Fort Wayne, Ind., assgnors, by mesne assignments, to The MagnavoxCompany, Fort Wayne, Ind., a corporation of Delaware Application May1,0, 1941, Serial No. 392,826

(Cl. Sil-2 8) 3 Claims.

This invention relates to a solenoid initiating mechanism and isparticularly applicable to machine guns of the Browning type and inwhich the sear is operated by a Sear-pin under vthe control ofasolenoid.

Considerable diiculties. have heretofore bee encountered with theabove-mentioned type of ring mechanism, exposed linkages and movingparts becoming coated with ice and frozen solid under certainatmospheric conditions, rendering the firing of the gun impossible.

'I'he position of the scar-pin on the gun must be very accuratelycontrolled when the gun is fired automatically and continuously and withpresent arrangements this accuracy of adjustment has been not only founddiiiicult to obtain, but also to maintain and this Primarily becausewith the use of a linkage between the point of adjustment and theSear-pin, particularly under varying climatic conditions, the play inthe linkage destroys any chance there is of obtaining, let alonemaintaining, an accurate adjustment.

Another difficulty is that this play in the linkage varies, dependingupon the position of the gun, so that although a gun may re perfectly inone position, it is apt to slow down when the gun is placed in adifferent position. Finally, where the gun is used in inaccessiblepositions, such as when employed on an airplane, the availability of theadjustment on the solenoid is important, but unfortunately this problemhas not heretofore been satisfactorily solved.

With the above diiiculties and disadvantages in mind, it is accordinglyan object of the present invention to provide a firing mechanism forautomatic rearms in which means are provided for adjusting the scar-pinwith relation to the sear with micromatic exactness.

A further object of the present invention is to provide a firingmechanism which will enable the gun to be fired at that exactpredetermined split second which will produce maximum efflciency andrecoil power.

A still further object of the invention is to provide a firing mechanismwhich will be positive in action, thereby avoiding misflring of thc gun,as so often happens in existing structures.

Again another object of the invention is to provide a structure whichcompletely encloses all of the moving parts and hence will be free fromthe influence of adverse atmospheric conditions. v

Another object is to provide a firing mechanism in which a direct drivewith no play is provided between the adjusting means and the sear pin.

y ing the application of the present invention to Still another objectis a construction in which the necessary adjustments can easily be madewith one hand of the operator, and which is readily accessible in remoteinstallations, .such as in airplanes.

The invention consists in the novel constructions, arrangements andmechanisms to be hereinafter described and claimed, for carrying out theabove stated objects and such other objects as will appear from thefollowing description of the accompanying drawings which illustrate, byway of example, the application of the invention to a machine gun of theBrowning type. The arrangement shown, however, is to be understood asillustrative only, and not as dening the limits of our invention.

In the drawings:

Fig. 1 is a longitudinal horizontal section showthe gun.

Fig. 2 is also a longitudinal horizontal section showing certain of theparts of the gun at the instant of scar release.

Fig. 3 is again a longitudinal horizontal section of certain parts ofthe gun and is included for the purpose of comparison.

Fig. 4 is a horizontal sectional view of the apparatus of the invention,but showing the parts in a position diierent from that in which they areshown in Fig. 1.

Fig. 5 is a top plan View of the device shown in Fig. 4.

Fig. 6 is a side elevation of the device shown in Fig. 5 looking in thedirection of the arrow.

Fig. 7 is a front view of the adjusting dial.

Fig. 8 is a view of the scar-operating pin disassembled.

Fig. 9 is a vertical sectional view of the core of the solenoid, and IFig. 10 is a vertical sectional view of the plunger of the solenoid andincludes the scar-operating pin.

Referring to the drawings, the machne gun shown therein comprises abreech casing which houses the breech mechanism, the casing being asusual rectangular in form and includes the two side plates 2, 2.

Projecting from the casing at the front is a barrel 4, which again asusual, upon recoil is movable rearward to a limited extent. The barrelextends rearwardly into a bearing Iil in the trunnion block 6. Connectedto the barrel 4 at the rear end thereof and bodily movable therewith isa barrel extension 8, said extension including two rearwardly extendingside members I0, and

on which are mounted for longitudinal movement independently thereof abreech bolt I2 in the well-known manner. The rear part I4 of the bolt isextended transversely so as to occupy the entire width o1' the casingbetween the two side plates 2, 2.

The breech bolt I2 has a central opening I6 therein adapted to receivethe firing pin I8.

At the rear of the breech bolt I2 is located a transversely andhorizontally movable sear 20. The sear has a forward extending hookportion 22 which is adapted to engage a locking shoulder 24 formed onthe ring pin I8.

All of the parts above described are standard in machine guns of theBrowning type, as is also the mechanism through the instrumentality ofwhich their relative operation is effected and hence it is thoughtunnecessary to include amore detailed description herein, as referencecan be had to Patent No. 1,293,021, issued February 4, 1919, to John M.Browning, for a more detailed description, as well as to various patentsissued subsequently thereto and such, for example, as Patent No.1,803,350, issued May 5, 1931, to George H. Tansley.

Coming now to the structure according to the present invention, in orderto bring about the operation of the sear 20 to effect release oi thefiring pin I8 at the exact predetermined split second, in one of theside plates 2, 2 of gun casing there is mounted the Sear-operatingmechanism designated generally by the reference 26. (See Fig. .1.)

'Such mechanism comprises a solenoid having a .base plate 30 at one sideof which is an integral projection 32 provided with a sloping face -34adapted to engage a cooperating face 36 forming one boundary of anopening 38 formed in the side plate 2 of the gun casing. The latter isalso provided with a second opening 40 having a sloping wall 42 toreceive a bolt 44 having a tapered base, said base being adapted to besecured in place between said sloping wall 42 and an opposed slopingWall on a projection 45 formed integral with the base plate 30. The boltprojects through an opening 41 in the base plate where it receives ashear nut 46 and by the screwing up of which on the bolt theSear-operating mechanism is secured rmly in place on the side plate 2.

The other side plate 2 is provided with similar openings 38 and 40,thereby making provision for the attachment of the operating mechanismto either side of the gun casing, as may be found necessary ordesirable.

The yoke 48 of the solenoid is secured to the base plate 30 by anysuitable means, such as screws 50. 52 indicates the iield coil or coilsof the solenoid, 54 the fixed core and 56 the plunger of the solenoid.Both the core 54 and plunger 56 are centrally bored to provide co-axialopenings '58 and I59 extending longitudinally thereof, respectively. Thejuxtaposed ends of the core 54 and plunger 56 are V-shaped in crosssection to afford co-operating surfaces 60, 62.

Within the openings 58, 59 is housed the searoperating assemblycomprising a pin assembly generally designated as 64 and a spring 65encompassing a portion of the pin assembly 64. By reference to Fig. 8 itwill be seen that the pin at one end is provided with an externallyscrew-threaded portion 66 which screws into the opening 58 (which iscooperatingly screwthreaded) in the plunger 56. spaced from the portion66 on the stem of the pin assembly is an internally threaded collar 68adapted to re- The reason for making the pin assembly in two parts is,o1 course, to enable the spring 65 to be slipped into place on the pinassembly 84. The head 14 is also formed with opposed flat faces 18whereby to prevent the pin assembly from rotating with relation to thecore 54 and plunger 56 by the means hereinafter described.

It will be seen from Fig. 6 that the base plate 30 is provided with acircular opening 80 to receive a stepped-back portion 82 of the core 54(see Fig, 9), which also has a semicircular portion 84 surmounting thestepped-back portion 82 and which projects into line with the outersurfaces of the projections 32 and 45 of the base plate 30. A flat-sidedopening 86 of reduced diameter is formed throughthe portions 82 and 84to provide a continuation of the opening 58. This opening 86 houses andguides the head 14, the nat faces 18 cooperating with the at sides ofthe opening 86, preventing the rotation of the pin assembly 64 withrelation to the core 54 and plunger 56. 1t will be observed that thereduced diameter of the opening 86 provides a shoulder 88 at one end ofthe opening 58 and it is against this shoulder that one end of thespring 65 presses (instead of against the underside of the head 14), theother end of the spring engaging the collar 68.

Means is provided for adjusting the position of the plunger 56 withrelation to that of the core 54 and -hence of controlling the amount ofmovement that will be imparted to the Sear-operating member, namely, thepin assembly 64, on its actuation by the solenoid. With this end inview, the plunger l56 adjacent its outer face is formed with a pair ofdiametrically opposed recesses 90 into which project pins 92, which, attheir outer ends, are secured to or formed integral with a. disc 94adapted to be rotated by an operating lever 96 which in turn isjournaled in a dish-shaped cap l98, the peripheral edges of which arexed to the yoke 48 in any suitable manner or by any convenient means.

As shown best in Fig. '1, on its outer face the cap 98 is provided witha plurality of spacedapart circumferentially arranged notches orrecesses |00 adapted to be engaged by the lever 96. In order to insurethat the lever, once it has been moved to engage a selected slot, willremain in engagement therewith, it is preferably made of spring metaland being bowed out in tension by the outer dished surface of the cap(see Fig. 5), will always spring into any slot with which it is broughtinto engagement |02 indicates diagrammatically the connection throughwhich the solenoid may be energized from any suitable source of Ipower,and this may include control from a remote station I04 through a cableor electrical conductor |06.

Coming now to the operation of the gun, it is believed unnecessary toeither illustrate or describe in detail the mechanism by which this iseffected, as this is identical with that usually employed in guns of thetype to which the invention is shown applied. Further, any well-knownmeans, and such as the spring |08, can be employed to bias the sear 20for movement in the direction to engage and hold the ring pin I8.

The operation of the sear 20 in the opposite direction, that is to say,to release the firing pin i8 from the sear hook 22, is brought about bythe Sear-operating pin assembly $4 of the present invention, the slopingor angularly disposed face llt providing a positive and accurate meansof operating the sear, and, what is more important, one by which therelease of the firing pin can be timed to that exact predetermined splitsecond to utilize fully the greatest recoil power and thus produce fullmaximum efciency of the gun.

This predetermined accurate timing of release of the ring pin i8 isenhanced by the means for" adjusting the extent or distance the slopingface it oi' the operating pin assembly t@ projects into the path of thesear 28, the pin assembly dj and said adjusting means in combinationproviding a micrometer adjustment of the former with relation to thesear 28. The micrometric timing of thering pin release will beappreciated when it is pointed out that the rotation of the lever 96from one notch i8() to the next adjacent notch can Ibe made to provide,for example, an adjustment of the Sear pin assembly 8f3 of the order of.003, Such rotation of the lever @t rotates the disc dii which in turnrotates the pins $2 and the plunger 58. As the pin assembly til isprevented from rotating relative to core 5d and plunger 5t, the pinassembly will be adjusted so that its head 'it Will project more or lessinto the path of the sear 2o depending upon the direction of rotation ofthe lever s6 and the extent of movement thereof.

The energization of the solenoid in the usual manner will, of course,move the plunger 56 from the position shown in Fig. 1 to that shown inFig. d to move pin assembly 64 from its inoperative to its operativeposition, the parts being returned to their inoperative position, on thedeenergization of the solenoid, by the spring 65.

In our experiments and investigations, we have ascertained that amachine gun can be made to operate at maximum eiiiciency if the Sear isreleased to in turn release the ring pin at a point when the mechanismin its forward motion is a certain distance from its extreme forwardposition of rest: in other words, before the barrelv extension 8contacts the rear face of the trunnion 6 of the gun in such forwardmotion.

In one application 'maximum eiiiciency has been found to be providedwhen the sear is operated to release the firing pin when the front raceof the extension 8 in its forward movement is .074 of an inch from therear face of the trunnion. This is villustrated in Fig. 2 which showsthe parts in the position which they occupy at the instant the iiringpin I8 is released, the bolt I2 is still moving forward and by the timethe .074 gap between the barrel extension 8 and lthe trunnion 6 iscovered, the firing pin contacts the primer and explosion occurs at theexact instant that the barrel extension 8 engages the rear face of thetrunnion.

By way of comparison, Fig. 3 can be referred to wherein, in the positionthere' shown, the sear pin has been adjusted to extend too far into thepath ofthe sear 20. Therefore, the sear 20 contacts the pin too early,with the result that firing will take place before the barrel extension8 has had time to come to rest against the trunnion, and loss of powerwill follow.

Of course, our improved solenoid may be utilized as an initiating oroperating means in connection with other devices, particularly wherepredetermined exact split second action is necessary or desirable.

i-Iaving thus described our invention, and shown one form of itsapplication, We claim:

. l. Firing pin release mechanism for automatic iirearms having a breechbolt, a transversely and horizontally movable sear carried by the breechbolt, and means for biasing the sear'in one direction to engage thefiring pin to hold it in cocked position, comprising a solenoid, meansfor energizing said solenoid, a fixed core and a cooperating plungerdisposed within said solenoid, a scar-operating pin housed within saidplunger and core and having an angularly'disposed :face adapted toengage the sear in its operative position, and means for adjusting theposition of said pin with relation to the sear, comprising pins mountedin openings in said plunger, a Iplate secured to said pins, a cap memberclosing the end of the solenoid, an adjustment lever secured to saidplate and pivotally mounted in said cap, and a plurality of notches inthe outer surface of said cap adapted to be engaged by said adjustmentlever.

2. Mechanism operating means comprising a solenoid, means for energizingsaid solenoid, a iixed core and a cooperating plunger disposed withinsaid solenoid, a pin assembly housed within said plunger and core andhaving an angularly disposed face adapted in its operative position toinitiate the operation of said mechanism, and means for adjusting theposition of said pin assembly with relation to said mechanism,comprising pins mounted in openings in said plunger, a plate secured tosaid pins, a cap member closing the end of the solenoid, an adjustmentlever secured to said platev and pivotally mounted in said cap, and aplurality of notches in the outer surface of said cap adapted to beengaged by said adjustment lever.

3. In a solenoid operating mechanism, a solenoid coil, a. xed coremounted within the solenoid and having .an opening therethroughextending axially of the solenoid, a pin received in said opening, saidopening and pin being constructed to permit rectilinear movement of saidpin in said opening and for preventing rotation thereof relative to thecore, a plunger in said solenoid, means for slidably and rotatablysupporting said plunger, means adjustably connecting said plunger tosaid pin for adjusting said pin axially oi the solenoid upon therotational adjustment of said plunger adjustably to predetermine thethrow of the pin, and rotary adjustment means for micrometricallyadjusting said plunger rotationally.

LA VERN EDWARD QUINN'ELI...

JOHN C. KOONZ.

